On the left, four through-hole USB-C connectors laid out on a purple cutting mat. On the right, a teardown picture shows that there's neither resistors nor CC connections inside such a connector, resulting in consequences described in the article.

The USB-C Connectors You Never Knew You Wanted To Avoid

On Tech Twitter, some people are known for Their Thing – for example, [A13 (@sad_electronics)], (when they’re not busy designing electronics), searches the net to find outstanding parts to marvel at. A good portion of the parts that they find are outstanding for all the wrong reasons. Today, that’s a through-hole two-pin USB Type-C socket. Observing the cheap tech we get from China (or the UK!), you might conclude that two 5.1K pulldown resistors are very hard to add to a product – this socket makes it literally impossible.

We’ve seen two-pin THT MicroUSB sockets before, sometimes used for hobbyist kits. This one, however, goes against the main requirement of Type-C connectors – sink (Type-C-powered) devices having pulldowns on CC pins, and source devices (PSUs and host ports) having pull up resistors to VBUS. As disassembly shows, this connector has neither of these nor the capability for you to add anything, as the CC pins are physically not present. If you use this port to make a USB-C-powered device, a Type-C-compliant PSU will not give it power. If you try to make a Type-C PSU with it, a compliant device shall (rightfully!) refuse to charge from it. The only thing this port is good for is when a device using it is bundled with a USB-A to USB-C cable – actively setting back whatever progress Type-C connectors managed to make.

As much as USB Type-C basics are straightforward, manufacturers get it wrong on the regular – back in 2016, a wrong cable could kill your $1.5k MacBook. Nowadays, we might only need to mod a device with a pair of 5.1K resistors every now and then. We can only hope that the new EU laws will force devices to get it right and stop ruining the convenience for everyone, so we can finally enjoy what was promised to us. Hackers have been making more and more devices with USB-C ports, and even retrofitting iPhones here and there. If you wanted to get into mischief territory and abuse the extended capabilities of new tech, you could even make a device that enumerates in different ways if you flip the cable, or make a “BGA on an FPC” dongle that is fully hidden inside a Type-C cable end!

Clever PCB Brings Micro USB To The Arduino Uno

Even with more and more devices making the leap to USB-C, the Arduino Uno still proudly sports a comparatively ancient Type-B port. It wouldn’t be a stretch to say that many Hackaday readers only keep one of these cables around because they’ve still got an Uno or two they need to plug in occasionally.

Looking to at least move things in the right direction, [sjm4306] recently set out to create a simple board that would let him mount a micro USB connector in place of the Uno’s original Type-B. Naturally there are no components on the PCB, it simply adapts the original through-hole footprint to the tight grouping of surface mount pads necessary to mount a female micro USB port.

Making castellated holes on the cheap.

The design is straightforward, but as [sjm4306] explains in the video below, there’s actually more going on here than you might think. Looking to avoid the premium he’d pay to have the board house do castellated holes, he cheated the system a bit by having the board outline go right through the center of the standard pads.

Under a microscope, you can see the downside of this approach. Some of the holes got pretty tore up as the bit routed out the edges of the board, with a few of them so bad [sjm4306] mentions there might not be enough of the pad left to actually use. But while they may not be terribly attractive, most of them were serviceable. To be safe, he says anyone looking to use his trick with their own designs should order more boards than they think they’ll actually need.

Of course you could go all the way and retrofit the Uno with a USB-C port, as we’ve seen done with devices in the past. But the latest-and-greatest USB interface can be a bit fiddly, especially with DIY gadgets, so we can’t blame him for going with the more reliable approach.

Continue reading “Clever PCB Brings Micro USB To The Arduino Uno”

Print-in-Place Connectors Aim To Make Wiring Easier

One thing some of us here in the United States have always been jealous of is the WAGO connectors that seem so common in electrical wiring everywhere else in the world. We often wonder why the electrical trades here haven’t adopted them more widely — after all, they’re faster to use than traditional wire nuts, and time is money on the job site.

Wago 221 compact lever connector via the Wago YouTube channel

This print-in-place electrical connector is inspired by the WAGO connectors, specifically their Lever Nut series. We’ll be clear right up front that [Tomáš “Harvie” Mudruňka’s] connector is more of an homage to the commercially available units, and should not be used for critical applications. Plus, as a 3D-printed part, it would be hard to compete with something optimized to be manufactured in the millions. But the idea is pretty slick. The print-in-place part has a vaguely heart-shaped cage with a lever arm trapped inside it.

After printing and freeing the lever arm, a small piece of 1.3-mm (16 AWG) solid copper wire is inserted into a groove. The wire acts as a busbar against which the lever arm squeezes conductors. The lever cams into a groove on the opposite wall of the cage, making a strong physical and electrical connection. The video below shows the connectors being built and tested.

We love the combination of print-in-place, compliant mechanisms, and composite construction on display here. It reminds us a bit of these printable SMD tape tamers, or this print-in-place engine benchmark.

Continue reading “Print-in-Place Connectors Aim To Make Wiring Easier”

This Debug Connector Brings Your Issues To The Edge

Given an unknown PCBA with an ARM processor, odds are good that it will have either the standard 10 pin 0.05″ or 20 pin 0.1″ debug connector. This uncommon commonality is a boon for an exploring hacker, but when designing a board such headers require board space in the design and more components to be installed to plug in. The literally-named Debug Edge standard is a new libre attempt to remedy this inconvenience.

The name “Debug Edge” says it all. It’s a debug, edge connector. A connector for the edge of a PCBA to break out debug signals. Card edge connectors are nothing new but they typically either slot one PCBA perpendicularly into another (as in a PCI card) or hold them in parallel (as in a mini PCIe card or an m.2 SSD). The DebugEdge connector is more like a PCBA butt splice.

It makes use of a specific family of AVX open ended card edge connectors designed to splice together long rectangular PCBAs used for lighting end to end. These are available in single quantities starting as low as $0.85 (part number for the design shown here is 009159010061916). The vision of the DebugEdge standard is that this connector is exposed along the edge of the target device, then “spliced” into the debug connector for target power and debug.

Right now the DebugEdge exists primarily as a standard, a set of KiCAD footprints, and prototype adapter boards on OSHPark (debugger side, target side). A device making use of it would integrate the target side and the developer would use the debugger side to connect. The standard specifies 4, 6, 8, and 10 pin varieties (mapping to sizes of available connector, the ‘010’ in the number above specifies pincount) offering increasing levels of connectivity up to a complete 1:1 mapping of the standard 10 pin ARM connector. Keep in mind the connectors are double sided, so the 4 pin version is a miniscule 4mm x 4.5mm! We’re excited to see that worm its way into a tiny project or two.

We’ve seen plenty of part-free debug and programming connectors before. Have a favorite? Let us know in the comments!

Milling A Custom 6-Pin DIN Connector

When [Charles Ouweland] found himself in need of a DIN connector that had a somewhat unusual pin arrangement, he figured he could fashion his own in less time than it would take to have a replacement shipped to him. In the end it sounds as though it took a lot longer than expected, but given the worldwide situation, we don’t doubt this bespoke connector was still put to work before its eBay counterpart would have arrived.

More importantly, the connector [Charles] produced looks fantastic. If we weren’t told otherwise, we’d have assumed the finished product was commercially produced. Although to be fair, he did have a little help there. The housing and pins themselves were pulled from a sacrificial connector; his primary contribution was the insulating block that holds the pins in their proper position.

So how did he make it? He had considered using a piece of scrap material and just putting the holes in it with a drill press, but he was worried getting the aliment right. Instead, he decided to call his cheap CNC router into service. By routing his design out of copper clad PCB, he was even able to tie the appropriate pins together right in the connector.

Admittedly, we don’t see a lot of hardware that still uses DIN connectors these days. But this tip is certainly worth filing away just in case. You never know when you might find an old piece of hardware that just needs a little TLC to get up and running again. Who knows, you might even find a dumpster full of them.

Magnets And Printed Parts Make Quick-Disconnect Terminals

The Apple MagSafe power connector is long gone from their product line, but that doesn’t mean that magnetic connectors aren’t without their charms. It just takes the right application, and finding one might be easier with these homebrew magnetic connectors.

We’ll admit that the application that [Wesley Lee] found for his magnetic connectors is perhaps a little odd. He’s building something called Linobyte, a hybrid art and electronics project that pays homage to computing history with very high-style, interactive core memory modules. The connectors are for the sense wire that is weaved through the eight toroids on each module, to program it with a single byte. Each connector has a 3D-printed boot that holds a small, gold-plated neodymium magnet with the sense wire soldered to it. A socket holds another magnet to the underside of a PCB. The magnet in the boot sticks to the PCB and makes contact with pads, completing the circuit. We know what you’re thinking: heating a magnet past the Curie point is a great way to ruin it. [Wesley] admits that happens, but it just makes the connection a little weaker, which works for his application. The short video below shows how he puts them together.

We can think of a couple of ways these connectors would be useful, and we really like the look of the whole project. It’ll be interesting to see where it goes, but in the meantime, brushing up on how magnets work could be fun. Continue reading “Magnets And Printed Parts Make Quick-Disconnect Terminals”

The BNC Connector And How It Got That Way

When I started working in a video production house in the early 1980s, it quickly became apparent that there was a lot of snobbery in terms of equipment. These were the days when the home video market was taking off; the Format War had been fought and won by VHS, and consumer-grade VCRs were flying off the shelves and into living rooms. Most of that gear was cheap stuff, built to a price point and destined to fail sooner rather than later, like most consumer gear. In our shop, surrounded by our Ikegami cameras and Sony 3/4″ tape decks, we derided this equipment as “ReggieVision” gear. We were young.

For me, one thing that set pro gear apart from the consumer stuff was the type of connectors it had on the back panel. If a VCR had only the bog-standard F-connectors like those found on cable TV boxes along with RCA jacks for video in and out, I knew it was junk. To impress me, it had to have BNC connectors; that was the hallmark of pro-grade gear.

I may have been snooty, but I wasn’t really wrong. A look at coaxial connectors in general and the design decisions that went into the now-familiar BNC connector offers some insight into why my snobbery was at least partially justified.

Continue reading “The BNC Connector And How It Got That Way”